This is impossible

Question

Please help, I jsut cant grasp this stuff :(
```loops.swift
let numbers = [2,8,1,16,4,3,9]
var sum = 0
var counter = 0
// Enter your code below
while counter < numbers.count {
counter +=  1
newValue = numbers.count()
sum = newValue +=1
}
```

Jennifer Nordell · Accepted Answer

Hi there!  I see that you've been trying so let's take a look at the solution step by step.  It's not impossible!
```swift
let numbers = [2,8,1,16,4,3,9]
var sum = 0
var counter = 0
// Enter your code below
while counter < numbers.count {
  sum += numbers[counter]
  counter += 1
}
```
Ok so we set up our while loop, which you did correctly as it passed step 1.  There must be some confusion about the next step.  We have a sum variable which is started at 0.  This makes sense as we haven't yet added anything to it.  What we're wanting to do is create a running total and keep track of it.
The numbers[counter] will pull a value from that index of the numbers array which is already set up for us.  Because we start with the counter at 0, the very first iteration will pull the number at the 0 index of the numbers array (which is 2) and add it to our sum.  This gives us a value of 2 for the sum.  Then we increment the counter which puts it at 1.
The next iteration will pull a value from numbers at the index of 1, because that is our current value of counter.  The number at the index of 1 is 8.  It is now added to sum, which gives it a value of 10.  This process will repeat until we've gotten every number out of the array and added its value to sum resulting in the sum of all elements of the array.
Hope this clarifies things! :sparkles:

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Sean Lafferty

Sean Lafferty

This is impossible

1 Answer

Jennifer Nordell

Jennifer Nordell

Sean Lafferty

Sean Lafferty